Nicotinamide-assisted fabrication of high-stability gold-palladium nanoparticles on carbon fiber cloth for hydrogen peroxide electroreduction

Abstract

Bimetallic nanoparticles with excellent activity and stability have been widely studied as H2O2 electroreduction catalysts. Hereby, we have successfully found a green fabrication of high-stability Au-Pd nanoparticles directly supported on carbon fiber cloth (Au-Pd NPs/CFC) by using tobacco extract (nicotinamide) as a simple and ecofriendly reducing agent. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction analyses and high angle annular dark field scanning TEM are performed to characterize the morphology, composition and structure of the as-prepared electrode. Results show that alloy nanoparticles prepared with different mole ratios of HAuCl4/PdCl2 mixtures in the wide range of 10–100nm have a uniform distribution on every carbon fiber, presenting a regular circle shape. The 3D electrode is directly applied as the electrocatalyst for H2O2 reduction in acid solution and does not introduce into any polymer binders. The catalytic performance is investigated by chronoamperometry and voltammetry, exhibiting desired catalytic performance and improved utilization than other representative nanomaterials recently reported. Furthermore, Au-Pd NPs do not aggregate after the whole test due to the effect of in-situ immobilization, showing a great significance for the application in fuel cells. A direct peroxide-peroxide fuel cell (DPPFC) using Au-Pd NPs/CFC cathode with Ni/Ni-foam anode acquires a maximum power density of 22.8mWcm−2. Electrochemical stability test through long-term potential cycles (>9h) further confirms the high durability of the electrode.